Skipping the Boost Ball: Geothermal Core

Climb to the second spinner in the room using whatever method you choose and
get on the little ring that's higher than the rest of the spinner (where it
meets the pole). Turn and face the third spinner. Now, this part is tricky.
Do a running L-Lock Space Jump over to it (as shown in the above left video). It's not as easy as it sounds. You
need to start your second jump before you begin to descend from your first.

Once you make it safely, morph into a ball and raise the spinner. To do this,
just get into the spinner and hold down. It should go up as long as you hold
down. If it doesn't raise on it's own to begin with, lay a bomb. Hold up to
keep from rolling out. As soon as the spinner sucks you back in, hold down.
It should work this time (as shown in the above right video). It should be noted that sometimes you have to hold
somewhere between down and down-left/right to get it to work.

Once the spinner is raised, jump on the little hump in the spider ball track.
Now, use a ghetto jump to get on top of the newly raised spinner. Walk over to
the edge of the platform closest to the bomb slot atop the second spinner pole.
Face the door that leads to Twin Fires (where the rock, box, and spire are).
Lock onto the Puddle Spore nearest you if your are facing in this direction.
Line yourself up on the point of the platform that is closest to the pole of
the second spinner. Now for the fun part. Perform a dash jump to the right.
As soon as you jump, hold forward. This will bend your jump towards the pole
and compensate for the horrible position of the lock-on point. As soon as you
get directly in front of the pole, hit L and jump forward. This should kill
all the momentum gained from the dash jump and carry you directly to the pole
(you may have to adjust yourself in mid-air by turning left or right). Right
before you come in contact with the pole, morph into a ball. The goal is to
get stuck on the lip of the bomb slot. This is much more difficult than it
seems. You have to hit this jump perfect. There is no room at all for error. This method is detailed in the below left video.

Once you raise the roof, exit the room (either door). Go through this room so
that the game will load the next room. Now, go back to Geo Core. Magically,
all the spinners are raised and the roof is still up. Just collect the Plasma
Beam as you normally would.

Another way of reaching the Bomb Slot is to use a so-called "Double L-Lock Space Jump." This involves reversing the Y-axis of the Analog Stick (accessible via the Options menu when you press the Start button while playing). Once the Y-axis has been reversed, simply L-Lock Space Jump at the Bomb Slot and press R (while still holding forward) to make Samus look up, then Space Jump again to give you an additional boost toward the Bomb Slot (as shown in the below right video).